anguslau 寫:I think the preferred design is to:
1) cut the mask with extra rim ~5mm, therefore making mask diameter ~10mm larger than outer diameter of dew shield
2) cut a ring with inner diameter ~0.5mm larger than outer diameter of dew shield
3) glue the above ring onto the mask so that we can just place the mask over the dew shield

I know this design may be slightly more expansive to make compared to the original design, but it should be a bit safer. funoooo, can you please see if the supplier can also quote a price for this design? Then people can decide which design and order accordingly.

Please note that my measurements for FSQ-106ED is different from that of Subaru for some reason. Subaru, can you please double check your measurements? Thanks!

Subaru 寫:Thanks funoooo for arranging this service for us.

I would suggest the Sky90, FSQ106ED and ε-180ED users to make their measurements and agree on the design, before the actual production. Or a prototype for each type to be built before the massive production.

The measure I did, was use a 卡尺 to measure the inside diameter of the dew shield.

I think Angus did make a point, if the mask is made too fit, it may scratch the paint inside the dew shield. If the mask is made by fixing outside the dew shield like those branded one, that worry may be reduced.

Another suggestion on the slots is, the slots should be made a bit longer than the objective diameter, so that the whole lens surface is covered, instead of some masks that just cover part of the objective. Please note the outer part of the objective do collect most lights which affect the focus the most.

I don't have a long enough 卡尺 to measure for ε-180ED, may be we need Angus' help to provide the measurement and suggestion.

funoooo, just want to confirm that I would like to order 4 masks, one for each of my scopes as specified earlier. But please ask vixen to make the mask outer diameter = outer diameter of my scope dew shields + 20mm. I do not need the little circles. Just the mask sheets please.